The invention relates to a device for mixing and dispensing multi-component compositions, in particular for dental purposes, with a cartridge with at least two cylindrical chambers arranged in parallel for receiving the components and in each case a plunger for discharging the components, the chambers having outlet openings which are covered by a cap, which has an outlet tube enclosing a mixing helix, the cap being movable from a position closing the outlet openings into a position releasing them.
A known device of this type, which however is not intended for dental purposes (EP 0319 135 A2), has two cylindrical chambers, in each of which one component is contained. The chambers are provided on their end face with openings which are closed by a cap. The cap has a sleeve-shaped outlet tube, which encloses a mixing helix. The cap initially closes the openings of the chamber. If the two-component composition is to be dispensed, the cap is pulled, so that it moves away a little from the cartridge with the two chambers and releases the outlet openings. With the aid of plungers in the chambers, on which pressure is exerted, the components can then be pressed into the cap and from there into the sleeve-shaped outlet tube. While passing through this outlet tube, the components are mixed by the mixing helix.
Such devices are also very expedient for dental purposes. There is no need to provide a separate closure cap that has to be removed and replaced with a cap which contains the outlet tube and the mixing helix. However, a disadvantage of such devices is that a separate manipulation is required for pulling the cap to bring it into the open position. This is not only laborious; there is also the risk of inadvertently pulling the cap off entirely. Problems also arise in the production of such already known devices. As far as possible, the same model of the cartridges is intended to be supplied with different caps. Depending on the intended application, straight or curved outlet tubes are required. These caps must then also be respectively provided with a mixing helix, making them relatively expensive parts. Furthermore, the fitting of the mixing helix in the cap is not entirely simple.
The object of the invention is to provide a device of the type stated at the beginning which can be operated easily and unproblematically and allows low-cost and practical mass production.